Use of TDCS with proprioceptive exercises to improve gait and balance in visually impaired children and preadolescents: a protocol for randomized clinical trial study

In the absence of information from the visual system, balance is guided by only two of the three afferent systems. If there is no early stimulation of these systems, blind children tend to become passive, which can have a negative impact on muscle tone, coordination and balance. The aim of the present study protocol is to investigate whether transcranial direct current stimulation (tDCS) can enhance the effects of static and dynamic proprioceptive exercises on gait and balance control in children and preadolescents with acquired or congenital visual impairment. This randomized controlled trial will be conducted in three phases, starting with a cross-sectional analysis, followed by a pilot study, and concluding with a full-scale clinical trial. The study will be conducted following approval from the institutional review board of Universidade Evangélica de Anápolis, Anápolis, GO, Brazil (certificate number:4610052.6.0000.5076). The study will be divided into three phases. Phase 1 will be a cross-sectional study to characterize gait, postural control and balance (static and dynamic) in the sample. Phase 2 will be a pilot study that will serve to determine the sample size in Phase 3. Both phases 2 and 3 will employ the same methods and will constitute a randomized, controlled, double- blind, clinical trial. The participants will be randomly divided into four groups: (G1) active tDCS + static proprioceptive exercises; (G2) sham tDCS + static proprioceptive exercises; (G3) active tDCS + dynamic proprioceptive exercises; (G4) sham tDCS + dynamic proprioceptive exercises. The results will be based on evaluations performed on three occasions [preintervention, postintervention (after ten treatment sessions) and 1-month follow-up] and will involve three-dimensional gait analysis as well as assessments of functional mobility functional and balance (static and dynamic). The expected outcomes of this study protocol include determining the postural differences, functional mobility, and static balance between children and pre-adolescents with congenital and acquired visual impairment and enable the establishment of new rehabilitation protocols.